Everyone wants to be happy, don’t they? Aristotle thought it was the goal of life. The Declaration of Independence states we have an alienable right to pursue it. There’s a nascent field of academic study, positive psychology, which tries to collect data on what causes it. Legions of people merrily sell their books or courses to help you find it – of course for a certain, I’m sure very reasonable, fee.

But what, actually, is it? What is ‘happiness’? What are we talking about? Somewhat bizarrely people are very happy to give, or sell, their advice on how to be happy without ever trying to say what it is. But how can we find something if we don’t know what we’re looking for?

A common response, even among happiness researchers, is to say defining it is it too hard and it’s not worth trying.

On the contrary I think we can both make sense of what happiness is and successfully pursue it.

This isn’t very straightforward to do though. Some philosophical clarification is necessary first. The first step is recognising we don’t have just one concept of happiness. We have two.

In one sense we use ‘happiness’ as a value term to talk about what is ultimately good for someone, what makes their life go well for them. ‘Happiness’ is akin to ‘well-being’ or ‘flourishing’ (or even ‘eudaimonia’ for the Aristotleans amongst you). Philosophers use the term ‘well-being’ and this is one I prefer. That something is ‘good for’ me doesn’t always means it’s good that I do it: it might be morally right to always tell the truth, even if that gets me in trouble.

In the other sense ‘happiness’ is a descriptive term for a set of psychological states. Here, ‘happiness’ is something like ‘joy’ or ‘contentment’ and the opposite of ‘misery’ and ‘sadness’.

It’s not surprising we often use the two senses of happiness interchangeably. It seems fairly reasonable to assume that a happy life (in the well-being sense) will involve feeling happy (the psychological state). However, we don’t have to think that way. You might think ignorance is bliss and only idiots can be happy. Or you might, as Aristotle did, believe what matters is being morally virtuous, not feeling good. To show how confusing talking about happiness can be it’s quite appropriate to say, according to Aristotle, happiness has nothing to do with happiness.

So, if we want to pursue happiness, we need to answer two questions:

1. What makes someone’s life go well?

2. What are the psychological states that make up happiness?

Let’s take these one at a time.

Philosophers don’t agree on many things, but they do agree there are three accounts of well-being.

The first is hedonism. This is the view that all that matters is that you enjoy your life. In other words, being ‘happy’ in the second, psychological sense of the word. Although people tend to associate this view with Jeremy Bentham, ancient Greek philosopher Epicurus is probably the original advocate.

The second is desire-satisfaction. On this, your life goes well if you get what you want. Quite straightforward.

The third is the objective list. The first two accounts are subjective: your well-being is determined by how you think or feel. In contrast, advocates of the objective list think what really matters are the facts of your life, regardless of how you feel about them. Knowledge, wisdom and friendship are typical candidates for this account.

What’s unhelpful is different academic fields tend to prefer different accounts of well-being. Worse, they tend not to recognise this. Psychologists like hedonism and think our lives go better if we feel happier. Economists are suspicious of feelings (which you’ll know if you’ve met one) and think we should just make people richer so they can satisfy more of their desires. In international development success is typically measured by improving things like health and literacy outcomes, rather than seeing if people feel more pleasure and less pain.

There’s obviously lots of arguments to be had over which account is the right one. There isn’t space for a proper discussion here, so I’ll condense the debate into a single point. Imagine someone who has got everything he ever wanted in life: he is wealthy, educated, good-looking, etc. (imagine Donald Trump, if Donald Trump were also educated and good-looking) but suffers from chronic, incurable depression. Do you think his life going well for him? Would you swap your life for his? How you answer the question reveals which account of well-being you prefer.

Obviously you don’t have to agree with me, but my inclination is to say that his life isn’t going well for him. I can’t see what the point is of meeting your desires, or achieving certain objective goals unless it makes you feel good. So I’m a hedonist. I think all that matters for happiness (in the well-being sense) is happiness (in the psychological sense). Many object to this position – among other things, it seems to imply we should plug ourselves into the Matrix if that would make us happier – and though I think I can meet those challenges, I won’t try here.

You might think that all the accounts collapse into thinking it’s important to feeling happy: happiness is something you desire amongst your other desires, or it might be one item on your objective list. But this misses the point that most people, most of the time, don’t pursue (psychological) happiness, but wealth and status. And I think they are making a mistake. I’d rather be a humble philosopher than a Monte Carlo playboy, but maybe that’s just because I find plutocrats dull and can’t stand caviar.

This brings me neatly onto the second question: what are the psychological states that make up happiness? Here, there are two possibilities.

We can think about feeling happiness as holding a positive evaluation of one’s life as a whole. This is the life satisfaction theory.

Alternatively, we can think of happiness as moment-to-moment experiences of pleasure and pain. Bentham famously put this forward, arguing happiness was just pleasure and a lack of pain. I think we could broaden this position and say that ‘pleasure’ is just anything that feels good to us. This can range from seemingly shallow pleasures such as sex, drugs and rock and roll, to more profound, fulfilling sensations such as those derived from intellectual study, bringing up children or working to help our fellow man.

This matches the two ways we can think about our lives. We can think about lives as a story: are we achieving the things we want to achieve? Or we can think about lives as something we experience one minute at a time.

Which sort of feelings of happiness we are interested in will depend on our views about well-being. Again I’ll simplify the debate. Imagine two lives: one which is extremely enjoyable but where, when you stop to think about it, you never quite feel satisfied (maybe you have very high standards) and another which you find very boring but very satisfying. Which would you pick?

I’d pick the first life. Moments where we evaluate our lives are moments just like any other. I’d rather have more good moments than fewer. Therefore I think happiness, the psychological state, is having experiences that feel good to us. I don’t think it gets trumped by a few moments of life satisfaction.

The pursuit of happiness doesn’t have to be mysterious. The only thing that matters for my life to go well, I think, is being happy. Happiness is about living a pleasurable, enjoyable, fulfilling life.

And how do we find such a life? Ah, now that’s a question for another time…